@article{03769944, title = {Spectral inequalities involving the sums and products of functions.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {5}, year = {1982}, pages = {141-157}, doi = {10.1155/S0161171282000143}, zbl = {0489.26010}, language = {en}, url = {http://dml.mathdoc.fr/item/03769944} }
Chong, Kong-Ming. Spectral inequalities involving the sums and products of functions.. International Journal of Mathematics and Mathematical Sciences, Tome 5 (1982) pp. 141-157. doi : 10.1155/S0161171282000143. http://gdmltest.u-ga.fr/item/03769944/